JP2005057508A - Apparatus and method for movement detection, apparatus and method for luminance signal/color signal separation, apparatus and method for noise reduction, and apparatus and method for video display - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To solve the problem that a luminance signal component leaks into a color signal component to cause a cross-color in a luminance signal/color signal separating apparatus using a movement detecting apparatus since a video signal including many oblique components is judged by the movement detecting apparatus to be a moving picture when inputted. <P>SOLUTION: The movement detecting apparatus is provided with a movement detecting circuit which detects movement quantities for each sample of the video signal from differences of the video signal between frames, an oblique correlation detecting circuit which detects a luminance component in an oblique direction by delaying sample points of precedent and following lines behind a video signal between lines by a delay circuit in the oblique direction, a judgment circuit which judges movements by switching a movement judgment level according to the output from the oblique correlation detecting circuit, and a switching circuit which switches an output of inter-line YC separation and an output of inter-frame YC separation according to the movement judgment result of the movement judgment circuit. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to an apparatus and method for detecting a motion amount from a video signal, a luminance signal / color signal separation apparatus and method to which the motion detection apparatus and method are applied, a noise reduction apparatus and method, and a video display apparatus and method.

  In recent years, with the increase in size and image quality of television receivers, it has become important to improve the performance of a luminance signal / color signal separation device that separates a luminance signal and a color signal from a composite video signal. Furthermore, a luminance / color signal separation device called three-dimensional YC separation switches between two-dimensional YC separation using line correlation and three-dimensional YC separation using frame correlation according to the motion detection result. High performance of the circuit is regarded as important.

  Hereinafter, a conventional motion detection device and luminance signal / color signal separation device will be described.

  FIG. 20 is a block diagram showing a configuration of a motion processing circuit disclosed in Japanese Patent Laid-Open No. 10-108039. In FIG. 20, the input composite video signal S1100 is sequentially supplied to the frame memory 1101 and the motion detection circuit 1102 as a current frame signal, and is further supplied to the first edge detection circuit 1103. The frame memory 1101 stores the current frame signal for one frame period, and then supplies the frame signal S1101 of the previous frame to the motion detection circuit 1102 and the second edge detection circuit 1104. The determination circuit 1105 includes an AND circuit that takes a logical product input from the first edge detection circuit 1103 and the second edge detection circuit 1104. The adaptive processing circuit 1106 attenuates the motion signal S1102 in accordance with the signal S1105 output from the determination circuit 1105.

  Next, the operation of the motion detection apparatus configured as described above will be described.

  FIG. 21 illustrates a case where the input signal S1100 includes a signal including an edge portion signal and the edge portion moves from the signal S1101 one frame before in the motion processing circuit illustrated in FIG. . The motion signal S1102 output from the motion detection circuit 1102 determines that the edge portion is moving. The first edge detection circuit 1103 and the second edge detection circuit 1104 detect the edge detection signals S1103 and S1104, respectively. However, since the edge portions do not overlap, the determination circuit 1105 sets the value of the output determination signal S1105 to 0. It is said. When the determination signal S1105 is 0, the motion signal S1102 is output as it is as the signal S1106.

FIG. 22 illustrates a case where a signal including an oblique component is input to the input signal S1100 in the motion processing circuit illustrated in FIG. Similar to FIG. 12, a motion signal S1106 is output.
JP-A-10-108039

  However, in the motion processing circuit described above, when an edge portion is detected, it is impossible to distinguish between a case where an oblique component is input and a case where an edge portion is input. Accordingly, when an oblique component is input, the amount of motion of the motion detection result cannot be corrected or attenuated.

  Further, when the above-described motion processing circuit is applied to a luminance signal / color signal separation device, two-dimensional YC separation using line correlation and inter-frame YC separation using frame correlation are performed according to the output signal of the motion processing circuit. The luminance signal / color signal separation device to be switched cannot switch between line correlation and frame correlation according to the amount of oblique components. That is, when the signal includes an oblique component, it is not possible to attenuate the amount of motion and determine “still” or change the threshold for motion determination. Therefore, when a signal containing a large amount of oblique components is input, it is not possible to reduce the cross color generated when the luminance component is mixed into the color component when the luminance signal and the color signal are separated from the composite video signal.

  An object of the present invention is to provide a motion detection apparatus and method that can improve motion detection accuracy when a signal including an oblique component is input.

  Another object of the present invention is to provide a luminance signal / color signal separating apparatus and method capable of reducing cross color due to a luminance signal component leaking into a color signal component even when a luminance signal correlated in an oblique direction is input. Is to provide.

  A motion detection apparatus according to the present invention includes a diagonal correlation detection unit that detects a correlation (diagonal correlation) in a diagonal direction of a composite video signal, a motion detection unit that detects a motion amount based on a difference between frames of the composite video signal, A motion determination unit that determines the presence or absence of motion in the composite video signal based on the amount of motion detected by the motion detection unit, the motion determination unit taking into account the detection result of the diagonal correlation by the diagonal correlation detection unit Then, the presence or absence of the movement is determined.

  Preferably, the motion determination unit sets a threshold value at a level corresponding to a detection result of the diagonal correlation by the diagonal correlation detection unit, and compares the motion amount detected by the motion detection unit with the threshold value. To determine the presence or absence of the movement.

  Preferably, the motion determination unit corrects the motion amount detected by the motion detection unit according to the detection result by the oblique correlation detection unit, and compares the corrected motion amount with a predetermined threshold value. The presence or absence of the movement is determined by

  Preferably, the motion determination unit determines that “there is motion” when the amount of motion detected by the motion detection unit is greater than a predetermined threshold, and the amount of motion is greater than the predetermined threshold. When it is small, the presence or absence of motion is determined according to the detection result of the diagonal correlation by the diagonal correlation detector.

  Preferably, the motion detection unit detects a motion amount based on a first motion detection circuit that detects a motion amount based on a difference between the frames of the composite video signal, and a difference between two frames of the composite video signal. And a second motion detection circuit.

  Preferably, the motion detection unit detects a motion amount based on a difference between one frame of luminance signals extracted from the composite video signal by luminance signal / color signal separation using line correlation. And a second motion detection circuit for detecting a motion amount based on a difference between one frame of color signals extracted from the composite video signal by luminance signal / color signal separation using the line correlation.

  Preferably, the motion determination unit includes a first motion determination circuit that determines presence or absence of motion in the composite video signal based on a motion amount detected by the first motion detection circuit, and the second motion detection. And a second motion determination circuit that determines the presence or absence of motion in the composite video signal based on the motion amount detected by the circuit.

  Preferably, the first and / or second motion determination circuit determines the presence or absence of the motion in consideration of a detection result of the diagonal correlation by the diagonal correlation detection unit.

  Preferably, the motion determination unit switches between a first determination and a second determination according to a detection result of the diagonal correlation by the diagonal correlation detection unit, and the first determination is performed by the first motion detection circuit. The second determination is performed based on the amount of motion detected by the first motion detection circuit and the second detection circuit. The presence or absence of the movement is determined based on the amount of movement.

  A luminance signal / color signal separation device according to the present invention includes a first luminance signal / color signal separation unit that extracts a first luminance signal and a first color signal from a composite video signal using line correlation, and a frame. A second luminance signal / color signal separation unit that extracts a second luminance signal and a second color signal from the composite video signal using correlation; the motion detection device; and the first luminance signal. And the second luminance signal are combined according to the determination result by the motion determination unit of the motion detection device and output as a third luminance signal, and the first color signal and the second color signal are And a switching unit that synthesizes and outputs a third color signal according to a determination result by the motion determination unit of the motion detection device.

  Another luminance signal / color signal separation device according to the present invention is a first luminance signal / color signal that extracts a first luminance signal and a first color signal using line correlation of a current frame of a composite video signal. A separation unit; a second luminance signal / color signal separation unit that extracts a second luminance signal and a second color signal using line correlation of a previous frame of the composite video signal; and the motion detection device described above And combining the first luminance signal and the second luminance signal according to the determination result by the motion determination unit of the motion detection device and outputting as a third luminance signal, and the first color signal And a switching unit that combines the second color signal with a result of determination by the motion determination unit of the motion detection device and outputs the second color signal as a third color signal.

  A noise reduction apparatus according to the present invention includes a first noise reduction unit that reduces noise of a composite video signal using line correlation, and a second noise reduction that reduces noise of the composite video signal using frame correlation. A determination result by the motion determination unit of the motion detection device, the motion detection device described above, the video signal obtained by the first noise reduction unit, and the video signal obtained by the second noise reduction unit And a switching unit that synthesizes and outputs the output according to the above.

  The motion detection method according to the present invention includes a step (a) of detecting a correlation (diagonal correlation) in an oblique direction of a composite video signal, and a step (b) of detecting a motion amount based on a difference between frames of the composite video signal. And (c) determining the presence or absence of motion in the composite video signal based on the amount of motion detected in the step (b). In the step (c), the diagonal correlation of the step (a) is performed. The presence / absence of the movement is determined in consideration of the detection result.

  Preferably, in the step (c), a threshold value of a level corresponding to the detection result of the diagonal correlation in the step (a) is set, and the amount of motion detected in the step (b) and the threshold value are set. To determine the presence or absence of the movement.

  Preferably, in step (c), the amount of motion detected in step (b) is corrected according to the detection result in step (a), and the corrected amount of motion is compared with a predetermined threshold value. To determine the presence or absence of the movement.

  Preferably, in the step (c), when the amount of motion detected in the step (b) is larger than a predetermined threshold, it is determined that there is a motion, and the amount of motion is determined to be the predetermined threshold. If smaller than, the presence / absence of motion is determined according to the detection result of the diagonal correlation in the step (a).

  Preferably, in the step (b), a motion amount is detected based on a difference between the frames of the composite video signal (d) and a motion amount is detected based on the difference between the frames of the composite video signal. Step (e).

  Preferably, the step (b) includes a step (d) of detecting a motion amount based on a difference between one frame of luminance signals extracted from the composite video signal by luminance signal / color signal separation using line correlation. And (e) detecting a motion amount based on a difference between one frame of color signals extracted from the composite video signal by luminance signal / color signal separation using the line correlation.

  Preferably, the step (c) is detected by the step (f) for determining the presence or absence of motion in the composite video signal based on the motion amount detected by the step (d) and the step (e). (G) determining the presence or absence of motion in the composite video signal based on the amount of motion.

  Preferably, in the step (f) and / or (g), the presence or absence of the motion is determined in consideration of the detection result of the diagonal correlation in the step (a).

  Preferably, in the step (c), the first determination and the second determination are switched according to the detection result of the diagonal correlation in the step (a), and the first determination is performed by the step (d). The presence / absence of the motion is determined based on the detected motion amount, and the second determination includes the motion amount detected by the step (d) and the motion amount detected by the step (e). The presence or absence of the movement is determined based on the above.

  The luminance signal / color signal separation method according to the present invention includes a step (h) of extracting a first luminance signal and a first color signal from a composite video signal using line correlation, and using the frame correlation. Step (i) of extracting a second luminance signal and a second color signal from the composite video signal, the above-described motion detection method, and the motion detection of the first luminance signal and the second luminance signal. According to the determination result in step (c) of the method, it is combined and output as a third luminance signal, and the first color signal and the second color signal are determined in step (c) of the motion detection method A step (j) of synthesizing according to the result and outputting as a third color signal.

  Another luminance signal / color signal separation method according to the present invention includes a step (k) of extracting a first luminance signal and a first color signal using line correlation of a current frame of a composite video signal, and the composite The step (l) of extracting the second luminance signal and the second color signal using the line correlation of the previous frame of the video signal, the motion detection method described above, the first luminance signal and the second luminance signal. Are synthesized according to the determination result in step (c) of the motion detection method and output as a third luminance signal, and the motion detection is performed on the first color signal and the second color signal. A step (m) of combining and outputting as a third color signal in accordance with the determination result in step (c) of the method.

  The noise reduction method according to the present invention includes a step (n) of reducing noise of a composite video signal using line correlation, a step (o) of reducing noise of the composite video signal using frame correlation, and And the video signal obtained in step (n) and the video signal obtained in step (o) are combined and output according to the determination result in step (c) of the motion detection method. Step (p).

  In the motion detection apparatus and method of the present invention, since the correlation in the oblique direction of the input composite video signal is detected and the motion determination is switched according to the detection result, the motion detection accuracy is improved in the video signal having a large correlation in the diagonal direction. Can be improved.

  Further, when the motion detection apparatus / method of the present invention is used in a luminance signal / color signal separation apparatus / method, the luminance signal / color signal separation between lines according to the motion judgment switched according to the detection result of the diagonal correlation. By switching between the luminance signal / color signal separation output between the output and the frame, a motion determination is performed on the signal containing a large amount of the oblique component rather than the frame correlation luminance signal / color signal separation. Therefore, a luminance signal component in an oblique direction such as an oblique line is input to the line correlation luminance signal / color signal separation unit and is not correctly separated in the line correlation luminance signal / color signal separation unit, and leaks into the line correlation output color signal. Even in this case, it is possible to reduce the cross color and improve the image quality in the output color signal.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. In the drawings, the same portions or corresponding portions are denoted by the same reference numerals, and description thereof will not be repeated.

(First embodiment)
<Overall configuration of television receiver>
FIG. 1 shows the overall configuration of a television receiver according to the first embodiment. The television receiver 10 includes a terrestrial tuner 1, an AV switch 2, a Y / C separation device 3, a color demodulation circuit 4, an RGB conversion circuit 5, a monitor screen 6, an audio processing circuit 7, An audio output circuit 8 and a speaker 9 are provided.

  The terrestrial tuner 1 receives a broadcast assigned to each channel. The AV switch 2 switches between a terrestrial broadcast S10 received by the tuner 1 and a video signal and an audio signal (Video input) input from an external device such as a video cassette recorder. The Y / C separator 3 separates the composite video signal S100 output from the AV switch 2 into a luminance signal S109 and a color signal S110. The color demodulation circuit 4 demodulates the color signal S110 output from the Y / C separation device 3 into a U signal S40U and a V signal S40V that are color difference signals. The RGB conversion circuit 5 converts the luminance signal S109 from the Y / C separation device 3 and the U signal S40U and V signal S40V from the color demodulation circuit 4 into an R signal S50R, a G signal S50G, and a B signal S50B. The monitor screen 6 displays an image from the R signal S50R, the G signal S50G, and the B signal S50B output from the RGB conversion circuit 5. The audio processing circuit 7 processes the audio signal S100A output from the AV switch 2. The audio output circuit 8 amplifies the audio signal S70 output from the audio processing circuit 7 and outputs it to the speaker 9. The speaker 9 outputs the audio signal S80 output from the audio output circuit 8.

<Internal configuration of Y / C separation device 3>
FIG. 2 shows an internal configuration of the Y / C separation device 3 shown in FIG. The Y / C separation device 3 includes line memories 101 and 102, a line correlation YC separation circuit 103, an oblique correlation detection circuit 104, a frame memory 105, a frame correlation YC separation circuit 106, a motion detection circuit 107, A motion determination circuit 108 and switching circuits 109 and 110 are provided.

  The line memory 101 delays the composite video signal S100 from the AV switch 2 (see FIG. 1) by one horizontal period and outputs it as a composite video signal S101. The line memory 102 delays the signal S101 from the line memory 101 by one horizontal period and outputs it as a composite video signal S102.

  The line correlation YC separation circuit 103 extracts the luminance signal S103Y and the color signal S103C based on the correlation between the composite video signals S100, S101, and S102 (correlation between three lines).

  The diagonal correlation detection circuit 104 detects a correlation (diagonal correlation) in the diagonal direction of the luminance signal component of the composite video signal, and outputs a signal S104 corresponding to the detected diagonal correlation.

  The frame memory 105 delays the composite video signal S101 from the line memory 101 by one frame period and outputs it as a composite video signal S105.

  The frame correlation YC separation circuit 106 extracts the luminance signal S106Y and the color signal S106C using the frame difference and frame addition of the video signals S101 and S105 between one frame.

  The motion detection circuit 107 detects a motion amount for each sample of the video signal from the difference between the video signals S101 and S105 between one frame, and outputs a signal S107 corresponding to the detected motion amount.

  The motion determination circuit 108 determines the presence or absence of motion of the composite video signal based on the signal S104 from the oblique correlation detection circuit 104 and the signal S107 from the motion detection circuit 107, and outputs a determination signal S108 according to the determination result. .

  The switching circuit 109 outputs the luminance signal S103Y from the line correlation YC separation circuit 103 or the luminance signal S106Y from the frame correlation YC separation circuit 106 as the luminance signal S109 in response to the determination signal S108 from the motion determination circuit 108. The switching circuit 110 outputs the color signal S103C from the line correlation YC separation circuit 103 or the color signal S106C from the frame correlation YC separation circuit 106 as the color signal S110 in response to the determination signal S108 from the motion determination circuit 108.

<Internal Configuration of Oblique Correlation Detection Circuit 104>
FIG. 3 shows an internal configuration of the oblique correlation detection circuit 104 shown in FIG. The oblique correlation detection circuit 104 includes bandpass filters 201, 202, 203, adders 204, 205, delay circuits 206, 207, subtractors 208, 209, absolute value circuits 210, 211, comparison circuits 212, 213 and an OR circuit 214.

  The bandpass filters 201, 202, and 203 are bandpass filters having a color subcarrier frequency of 3.58 MHz as a center frequency. The delay circuits 206 and 207 delay the signals S204 and S205 from the adders 204 and 205 at a clock frequency that is four times the color subcarrier frequency. The subtracter 208 subtracts the output S207 of the delay circuit 207 from the output S204 of the adder 204. The subtracter 209 subtracts the output S206 of the delay circuit 206 from the output S205 of the adder 205. The absolute value circuit 210 takes the absolute value of the output S208 of the subtracter 208 and outputs it as a signal S210. The absolute value circuit 211 takes the absolute value of the output S209 of the subtractor 209 and outputs it as a signal S211. Comparison circuits 212 and 213 compare signals S210 and S211 from absolute value circuits 210 and 211 with reference value S200, and output signals S212 and S213 corresponding to the comparison results. The OR circuit 214 outputs a logical sum of the outputs S212 and S213 of the comparison circuits 212 and 213.

<Operation of Y / C Separator 3>
Next, the operation of the Y / C separation device 3 configured as described above will be described.

  The input composite video signal S100 is input to the line memories 101 and 102, and a composite video signal S101 delayed by one line and a composite video signal S102 delayed by one line (two lines) are obtained.

  The composite video signals S100, S101, and S102 between the three lines are band-limited by a band-pass filter having a pass frequency band centered at 3.58 MHz by the line correlation color separation circuit 103, and the correlation of the color signals between the three lines is further determined. By taking a majority vote or an intermediate value for determination, a three-line correlated color signal S103C and a three-line correlated luminance signal S103Y are obtained.

  The composite video signal S101 delayed by one line is input to the frame memory 105, and the composite video signal S105 of the previous frame is obtained. A frame correlation luminance signal S106Y and a frame correlation color signal S106C are obtained by adding and subtracting the composite video signals S101 and S105 having a difference of one frame period by the inter-frame YC separation circuit 106.

  On the other hand, composite video signals S100, S101, and S102 between the three lines are input to the diagonal correlation detection circuit 104. The input composite video signals S100, S101, and S102 are band-limited by a bandpass filter having a pass frequency band centered on 3.58 MHz, respectively, and signals S201, S202, and S203 band-limited about 3.58 MHz are obtained. It is done. Since the phase of the color is inverted by 180 degrees between the lines, the adder 504 adds the band limit signal S202 of the center line and the band limit signal S201 having a difference between one line, thereby canceling out the color signal components. The obtained luminance component signal S204 is obtained. Similarly, the adder 205 adds the band limit signal S202 of the central line and the band limit signal S203 having a difference of one line by the adder 205, thereby canceling the color signal components and obtaining the band limited luminance component signal S205. The band-limited luminance component signals S204 and S205 are delayed by clock units by delay circuits 206 and 207, respectively, to obtain luminance component signals S206 and S207. By subtracting a difference between the band-limited luminance component signal S204 and the delayed luminance signal component signal S207 by the subtracter 208, the first diagonal correlation of the luminance signal component is obtained from the difference of the sample points shifted in the diagonal direction. A value S208 is obtained. The absolute value of the first correlation value S208 is acquired by the absolute value circuit 210, and a first diagonal difference value S210 is obtained. The difference value S210 in the first diagonal direction is compared with the diagonal component determination level S200. When the difference value S210 is smaller than the diagonal component determination level S200, it is determined that there is a correlation in the diagonal direction. The first oblique correlation signal S212 shown is output. When the difference value S210 is greater than the diagonal component determination level S200, it is determined that there is no correlation in the diagonal direction, and the comparison circuit 212 outputs a first diagonal correlation signal S212 indicating no correlation. Further, in order to detect a component opposite to the above-described oblique component, the subtractor 209 obtains a difference between the band-limited luminance component signal S205 and the delayed luminance signal component signal S206 in the oblique direction. A correlation value S209 in the oblique direction of the luminance signal component is obtained from the difference between the shifted sample points. The absolute value of the second correlation value S209 is acquired by the absolute value circuit 211, and a second diagonal difference value S211 is obtained. The difference value S211 in the second diagonal direction is compared with the diagonal component determination level S200. When the difference value S211 is smaller than the diagonal component determination level S200, it is determined that there is a correlation in the diagonal direction, and the comparison circuit 213 determines that there is a correlation. The second oblique correlation signal S212 shown is output. When the difference value S211 is greater than the diagonal component determination level S200, it is determined that there is no correlation in the diagonal direction, and the comparison circuit 213 outputs a second diagonal correlation signal S213 indicating no correlation.

  Based on the composite video signal S101 having a difference of one frame period and the composite video signal S105, the motion detection circuit 107 detects a motion amount and outputs a motion signal S107 corresponding to the detected motion amount. The motion determination circuit 108 compares the motion signal S107 with a predetermined threshold according to the oblique correlation detection signal S104, and outputs a determination signal S108 according to the comparison result.

  An example of the internal configuration of the motion determination circuit 108 is shown in FIG. The motion determination circuit 108 includes a selector 1081 and a determination unit 1082. The selector 1081 selectively gives threshold values Th1 and Th2 (Th1 <Th2) to the determination unit 1082 in accordance with the signal S104 from the oblique correlation detection circuit 104. Here, when the diagonal correlation detection circuit 104 determines that there is “diagonal correlation”, a signal S104 having a value “1” is provided to the selector 1081, and when it is determined that there is no diagonal correlation, a signal having a value “0”. Assume that S104 is given to the selector 1081. The selector 1081 provides the threshold value Th1 to the determination unit 1082 when the value of the signal S104 is “0”, and provides the threshold value Th2 to the determination unit 1082 when the value of the signal S104 is “1”. When the signal S107 from the motion detection circuit 107 is larger than the threshold value from the selector 1081, the determination unit 1082 determines “There is motion (moving image)” and outputs a determination signal S108 having a value “1”. On the other hand, when the signal S107 is smaller than the threshold value from the selector 1081, it is determined that “no motion (still image)”, and a determination signal S108 having a value “0” is output. As shown in FIG. 5, the motion determination circuit 108 increases the threshold for determining the presence or absence of motion when “with diagonal correlation” (TH1 → Th2), thereby “no motion (still image)”. ”(The range of the level of the signal S107).

  When the value of the determination signal S108 from the motion determination circuit 108 is “1” (that is, when it is determined that “motion exists (moving image)”), the switching circuit 109 uses the luminance signal S103Y from the line correlation YC separation circuit 103 as the luminance. The switching circuit 110 outputs the color signal S103C from the line correlation YC separation circuit 103 as the color signal S110. On the other hand, when the value of the determination signal S108 from the motion determination circuit 108 is “0” (that is, “no motion (still image)” is determined), the switching circuit 109 receives the luminance signal from the frame correlation YC separation circuit 106. S106Y is output as the luminance signal S109, and the switching circuit 110 outputs the color signal S106C from the frame correlation YC separation circuit 106 as the color signal S110.

  FIG. 6 is a waveform diagram of each signal when a diagonal line is input. The composite video signals S100, S101, and S102 are input with diagonal lines, and the correlation between the lines is low. If YC separation is performed between the lines, a calculation error is likely to occur, and a lot of cross colors are generated. When the composite video signal S101 and the composite video signal S105 one frame before move as shown in FIG. 6, the motion detection circuit 107 obtains the motion signal S107. On the other hand, the diagonal correlation detection circuit 104 detects diagonal components from the composite video signals S100, S101, and S102 of the current frame, and outputs a signal S104 indicating "with diagonal correlation" while the diagonal components are detected. As described above, when “with diagonal correlation” (that is, when the signal S104 has the value “1”), the motion determination circuit 108 increases the threshold for determining the presence or absence of motion (TH1 → Th2). The range determined as “no motion (still image)” (the level range of the signal S107) is expanded. For this reason, the motion determination signal S108 during the period when the oblique component is detected indicates “no motion (still image)”. In response to this, the switching circuit 109 outputs the luminance signal S106Y from the frame correlation YC separation circuit 106 as the luminance signal S109, and the switching circuit 110 outputs the color signal S106C from the frame correlation YC separation circuit 106 as the color signal S110. . As described above, when an oblique component is input, the cross color can be reduced by switching to YC separation between frames.

<Effect>
As described above, in the first embodiment, the diagonal correlation detection circuit 104 detects the diagonal correlation of the luminance signal component from the video signal between the three lines of the input composite video signal, and the diagonal correlation detection circuit 104 According to the detection result, the motion determination circuit 108 performs motion determination on the output signal S107 of the motion detection circuit 107 from the still image (when there is an oblique correlation, the threshold for determining the presence or absence of motion is increased). . Therefore, even when the diagonal luminance signal component is leaked to the line correlation output color signal S103C without being correctly separated by the line correlation YC separation circuit 103 in the composite video signals S100, S101, and S102, the diagonal line is inputted. By using frame correlation YC separation, it is possible to reduce the cross color in the output color signal S110 and improve the image quality. In addition, when a diagonal component is input, it is possible to prevent a motion detection result from being erroneously detected and to improve motion detection accuracy.

<Modification>
Here, a television receiver is taken up as an example of a device (video signal processing device, video display device) equipped with the Y / C separation device 3, but a liquid crystal television, a plasma display television, an organic EL television, a video capture board device, A personal computer or video cassette recorder may be used.

  The switching circuits 109 and 110 simply switch between the inter-line operation result (output of the line correlation YC separation circuit 103) and the inter-frame operation result (output of the inter-frame YC separation circuit 106). The calculation result between frames may be weighted and added by changing the composition ratio or changing the signal ratio.

  Further, instead of the motion determination circuit 108 having the internal configuration shown in FIG. 4, the motion determination circuit 108 having the internal configuration shown in FIG. 7 may be used. In the motion determination circuit 108 having the configuration shown in FIG. 4, when the diagonal correlation detection circuit 104 determines that there is an oblique correlation, the presence / absence of motion is set to a still image by increasing the threshold value. On the other hand, in the motion determination circuit 108 having the internal configuration shown in FIG. 7, the motion amount S107 detected by the motion detection circuit 107 is added to the diagonal component amounts S210 and S211 detected by the diagonal correlation detection circuit 104. Attenuation is performed at 1083, and the determination unit 1082 compares this with a fixed threshold value Th1 to determine the presence or absence of motion.

  Further, the motion determination circuit 108 that determines the presence or absence of motion according to the flow shown in FIG. 8 may be used. In the determination flow shown in FIG. 8, first, the motion amount S107 detected by the motion detection circuit 107 is compared with a fixed threshold value Th1 (ST101). When the amount of motion S107 is larger than the threshold value Th1, it is determined that “there is motion (moving image)” and a determination signal S108 corresponding to this is output. When the motion amount S107 is smaller than the threshold value, the presence / absence of motion is determined according to the presence / absence of diagonal correlation (ST102). When it is determined by the diagonal correlation detection circuit 104 that there is no “diagonal correlation”, it is determined that “there is motion (moving image)” and a determination signal S108 corresponding to this is output. On the other hand, when the diagonal correlation detection circuit 104 determines that there is “diagonal correlation”, it determines that “no motion (still image)” and outputs a determination signal S108 corresponding thereto.

(Second Embodiment)
<Internal configuration of Y / C separation device 3>
FIG. 9 shows an internal configuration of the Y / C separation device 3 according to the second embodiment. The Y / C separation device 3 further includes a frame memory 300, a motion detection circuit 301, a motion determination circuit 302, and a synthesis circuit 303 in addition to the configuration requirements shown in FIG. The frame memory 300 delays the composite video signal S105 from the frame memory 105 by one frame period and outputs it as a composite video signal S300. The motion detection circuit 300 detects the motion amount for each sample of the video signal from the difference between the video signals S101 and S300 between the two frames, and outputs a signal S301 corresponding to the detected motion amount. Similar to the motion determination circuit 108, the motion determination circuit 302 determines the presence / absence of a motion of the composite video signal based on the signal S104 from the oblique correlation detection circuit 104 and the signal S301 from the motion detection circuit 301. A corresponding determination signal S302 is output. The combining circuit 303 combines (OR operation) the determination signal S108 from the motion determination circuit 108 and the determination signal S302 from the motion determination circuit 302, and outputs the result as a determination signal S303. The switching circuit 109 outputs the luminance signal S103Y from the line correlation YC separation circuit 103 or the luminance signal S106Y from the frame correlation YC separation circuit 106 as the luminance signal S109 in response to the determination signal S303 from the synthesis circuit 303. The switching circuit 110 outputs the color signal S103C from the line correlation YC separation circuit 103 or the color signal S106C from the frame correlation YC separation circuit 106 as the color signal S110 in response to the determination signal S303 from the synthesis circuit 303.

<Operation of Y / C Separator 3>
Next, the operation of the Y / C separation device 3 configured as described above will be described.

  As in the first embodiment, the motion detection circuit 107 detects a motion amount based on the composite video signal S101 and the composite video signal S105 having a difference of one frame period, and generates a motion signal S107 corresponding to the detected motion amount. Output. The motion determination circuit 108 compares the motion signal S107 with a predetermined threshold according to the oblique correlation detection signal S104, and outputs a determination signal S108 according to the comparison result. Here, it is assumed that the motion determination circuit 108 has the same internal configuration as shown in FIG. As shown in FIG. 10, the motion determination circuit 108 sets a large threshold for motion determination when the diagonal correlation detection circuit 104 determines that there is diagonal correlation, and moves when it is determined that there is no diagonal correlation. A threshold value for determination is set small (ST201). Next, the set threshold value is compared with the motion amount S107. When the motion amount S107 is larger than the threshold value, it is determined as a moving image, and when the motion amount S107 is smaller than the threshold value, it is determined as a still image. (ST202). As described above, the motion determination circuit 108 increases the threshold for determining motion when an oblique correlation is detected, so that the motion determination result signal S108 is determined from a still image.

  On the other hand, the motion detection circuit 301 detects a motion amount based on the composite video signal S101 and the composite video signal S300 having a two-frame period difference, and outputs a motion signal S301 corresponding to the detected motion amount. The motion determination circuit 302 compares the motion signal S301 with a predetermined threshold according to the oblique correlation detection signal S104, and outputs a determination signal S302 according to the comparison result. Here, it is assumed that the motion determination circuit 302 has the same internal configuration as shown in FIG. As shown in FIG. 10, the motion determination circuit 302 sets a large threshold for motion determination when the diagonal correlation detection circuit 104 determines that there is diagonal correlation, and moves when it is determined that there is no diagonal correlation. A threshold value for determination is set small (ST301). Next, the set threshold value is compared with the motion amount S301. When the motion amount S301 is larger than the threshold value, it is determined as a moving image, and when the motion amount S301 is smaller than the threshold value, it is determined as a still image. (ST302). As described above, when the diagonal correlation is detected, the motion determination circuit 302 increases the threshold for determining the motion so that the motion determination result signal S302 is determined from the still image.

  The motion determination signals S108 and S302 are combined by the synthesis circuit 303 and provided to the switching circuits 109 and 110 as the determination signal S303. The switching circuit 109 switches between the luminance signal S103Y for the inter-line calculation and the luminance signal S106Y for the inter-frame calculation based on the determination signal S303. The switching circuit 110 switches between the color signal S103C for line-to-line calculation and the color signal S106C for frame-to-frame calculation based on the determination signal S303.

<Effect>
As described above, in the second embodiment, the diagonal correlation detection circuit 104 detects the diagonal correlation of the luminance signal component from the video signals S100, S101, and S102 between the three lines of the input composite video signal. In accordance with the detection result of the correlation detection circuit 104, the output signal S107 of the 1-frame motion detection circuit 107 is subjected to motion determination from the still image by the 1-frame motion determination circuit 108, and the output signal S301 of the 2-frame motion detection circuit 301 is detected. The two-frame motion determination circuit 302 determines the motion from the still image. Therefore, in the signals S100, S101, and S102 input to the three-line correlation YC separation circuit 103, the luminance signal component in the oblique direction is input to the line correlation YC separation circuit 103, and is not correctly separated by the line correlation YC separation circuit 103. Even when leaking into the correlation output color signal S103C, when a diagonal line is input, the cross color can be reduced in the output color signal S119 by using frame correlation YC separation, and the image quality can be improved.

  Further, by correcting the motion detection result between two frames from the still image according to the diagonal correlation detection result, in addition to improving the accuracy of motion detection of the luminance signal from the one frame difference, the video signal from the two frame difference is improved. The accuracy of motion detection in all bands can be improved, the motion detection result is less likely to be erroneously detected when an oblique component is input, the motion detection accuracy of the luminance signal of 1 frame difference is improved, and the video by 2 frame difference It is possible to improve the motion detection accuracy of the entire signal band.

<Modification>
As described in the modification of the first embodiment, the motion determination circuits 108 and 302 having the internal configuration shown in FIG. 7 may be used instead of the motion determination circuits 108 and 302 having the internal configuration shown in FIG. Good.

  Moreover, you may use the motion determination circuits 108 and 302 which determine the presence or absence of a motion according to the flow shown in FIG. In the determination flow shown in FIG. 11, first, the motion amounts S107, S301 detected by the motion detection circuits 107, 301 are compared with a fixed threshold value Th1 (ST101, ST501). When the motion amounts S107 and S301 are larger than the threshold value Th1, it is determined that “there is motion (moving image)”, and determination signals S108 and S302 corresponding thereto are output. When the motion amounts S107 and ST301 are smaller than the threshold value, the presence or absence of motion is determined according to the presence or absence of the diagonal correlation (ST102 and ST502). When the diagonal correlation detection circuit 104 determines “no diagonal correlation”, it determines “with motion (moving image)” and outputs determination signals S108 and ST302 according to this. On the other hand, when it is determined by the diagonal correlation detection circuit 104 that there is “diagonal correlation”, “no motion (still image)” is determined, and determination signals S108 and ST302 corresponding thereto are output.

(Third embodiment)
<Internal configuration of Y / C separation device 3>
FIG. 12 shows an internal configuration of the Y / C separation device 3 according to the third embodiment. The Y / C separation device 3 includes a motion determination circuit 304 instead of the motion determination circuit 108 shown in FIG. Other configurations are the same as those of the Y / C separation device 3 shown in FIG. The motion determination circuit 304 compares the motion amount S107 detected by the motion detection circuit 107 with a fixed threshold value, and outputs a determination signal S304 according to the result. The combining circuit 303 combines (OR operation) the determination signal S304 from the motion determination circuit 304 and the determination signal S302 from the motion determination circuit 302, and outputs the result as a determination signal S303.

<Operation of Y / C Separator 3>
Next, the operation of the Y / C separation device configured as described above will be described.

  The composite video signal S105 delayed by one frame is further delayed by one frame by the frame memory 300, the amount of motion is detected by the motion detection circuit 301 between the two frames from the composite video signals S101 and S300 having a difference of two frame periods, A two-frame motion signal S301 is output. The two-frame motion determination circuit 302 attenuates or corrects the motion signal S301 according to the diagonal correlation detection signal S104. When an oblique component is detected, the motion determination result signal S302 is determined from a still image by attenuating the amount of motion or increasing a threshold for determining motion for determining motion. The switching circuit 109 switches between the luminance signal S103Y for line-to-line calculation and the luminance signal S106Y for frame-to-frame calculation according to the motion determination result signal S303. The switching circuit 110 switches between the color signal S103C for line-to-line calculation and the color signal S106C for frame-to-frame calculation according to the motion determination result signal S303.

<Effect>
According to this embodiment, the diagonal correlation detection circuit 104 detects the diagonal correlation of the luminance signal component from the video signals S100, S101, S102 between the three lines of the input composite video signal, and this diagonal correlation detection circuit. Depending on the detection result of 104, the output signal S301 of the 2-frame motion detection circuit 301 is attenuated or corrected by the 2-frame motion determination circuit 302, and the motion is determined from the still image to be input to the 3-line YC separation circuit 103. Even in the signals S100, S101, and S102, the luminance signal component in the oblique direction is input to the line correlation YC separation circuit 103, and is not correctly separated by the line correlation YC separation circuit 103, but leaks to the line correlation output color signal S103C. By using frame correlation YC separation when diagonal lines are input The cross-color reduction in a color signal S110 which is force, it is possible to improve the image quality. Also, by attenuating or correcting the motion detection result between two frames according to the diagonal correlation detection result, the accuracy of motion detection of the entire band of the video signal based on the two-frame difference can be improved, and the diagonal component is input. In this case, it is possible to prevent the motion detection result from being erroneously detected and to improve the motion detection accuracy of the entire band of the video signal.

(Fourth embodiment)
<Internal configuration of Y / C separation device 3>
FIG. 13 shows an internal configuration of the Y / C separation device 3 according to the fourth embodiment. The Y / C separation device 3 includes a motion determination circuit 305 instead of the motion determination circuit 302 shown in FIG. Other configurations are the same as those of the Y / C separation device 3 shown in FIG. The motion determination circuit 305 compares the motion amount S301 detected by the motion detection circuit 301 with a fixed threshold value, and outputs a determination signal S305 according to the result. The combining circuit 303 combines (OR operation) the determination signal S108 from the motion determination circuit 108 and the determination signal S305 from the motion determination circuit 305, and outputs the result as a determination signal S303.

<Operation of Y / C Separator 3>
Next, the operation of the Y / C separation device configured as described above will be described.

  The composite video signal S101 is delayed by one frame by the frame memory 105, the amount of motion is detected by the inter-frame motion detection circuit 107 from the composite video signals S101 and S105 having a difference of one frame period, and the one-frame motion signal S107 is obtained. Output. The one-frame motion determination circuit 108 attenuates or corrects the motion signal S107 according to the diagonal correlation detection signal S104. When an oblique component is detected, the motion determination result signal S108 is determined from a still image by attenuating the motion amount or increasing the threshold value for determining motion. The composite video signal S105 delayed by one frame is further delayed by one frame by the frame memory 300, the amount of motion is detected by the motion detection circuit 301 between the two frames from the composite video signals S101 and S300 having a difference of two frame periods, A two-frame motion signal S301 is output. The inter-frame motion determination signal S108 and the inter-frame motion determination signal S305 are combined by the synthesis circuit 303. The switching circuit 109 switches between the luminance signal S103Y for line-to-line calculation and the luminance signal S106Y for frame-to-frame calculation according to the motion determination result signal S303. The switching circuit 110 switches between the color signal S103C for line-to-line calculation and the color signal S106C for frame-to-frame calculation according to the motion determination result signal S303.

<Effect>
According to this embodiment, the diagonal correlation detection circuit 104 detects the diagonal correlation of the luminance signal component from the video signals S100, S101, S102 between the three lines of the input composite video signal, and this diagonal correlation detection circuit. In accordance with the detection result 104, the output signal S107 of the 1-frame motion detection circuit 107 is attenuated or corrected by the 1-frame motion determination circuit 108, and the motion is determined from the still image to be input to the 3-line YC separation circuit 103. Even in the signals S100, S101, and S102, the luminance signal component in the oblique direction is input to the line correlation YC separation circuit 103, and is not correctly separated by the line correlation YC separation circuit 103, but leaks to the line correlation output color signal S103C. By using frame correlation YC separation when diagonal lines are input The cross-color reduction in a color signal S110 which is force, it is possible to improve the image quality. Also, by attenuating or correcting the inter-frame motion detection result in accordance with the diagonal correlation detection result, the accuracy of the luminance signal motion detection can be improved from the one-frame difference, and the motion is detected when an oblique component is input. The detection result is less likely to be erroneously detected, and the motion detection accuracy of the luminance signal of the difference of one frame can be improved.

(Fifth embodiment)
<Internal configuration of Y / C separation device 3>
FIG. 14 shows an internal configuration of the Y / C separation device 3 according to the fifth embodiment. The Y / C separation device 3 includes motion determination circuits 304 and 305 and a selector 601 instead of the motion determination circuits 108 and 302 and the synthesis circuit 303 shown in FIG. Other configurations are the same as those of the Y / C separation device 3 shown in FIG. The motion determination circuits 304 and 305 compare the motion amounts S107 and S301 detected by the motion detection circuits 107 and 301 with a fixed threshold value, and output determination signals S304 and S305 corresponding to the results. The selector 601 outputs the determination signal S304 from the motion determination circuit 304 to the switching circuits 109 and 110 as the determination signal S601 when the signal S104 from the oblique correlation detection circuit 104 indicates “there is an oblique correlation”. When the signal S104 from 104 indicates “no diagonal correlation”, the determination signal S304 from the motion determination circuit 304 and the determination signal S305 from the motion determination circuit 305 are combined (OR operation) and used as a determination signal S601 as a switching circuit. 109 and 110.

<Operation of Y / C Separator 3>
Next, the operation of the Y / C separation device configured as described above will be described.

  The composite video signal S101 is delayed by one frame by the frame memory 105, the amount of motion is detected by the inter-frame motion detection circuit 107 from the composite video signals S101 and S105 having a difference of one frame period, and the one-frame motion signal S107 is obtained. Output. The composite video signal S105 delayed by one frame is further delayed by one frame by the frame memory 300, the amount of motion is detected by the motion detection circuit 301 between the two frames from the composite video signals S101 and S300 having a difference of two frame periods, A two-frame motion signal S301 is output. The inter-frame motion determination signal S304 and the inter-frame motion determination signal S305 are output by the selector 601 when the diagonal correlation is present, and the inter-frame motion determination signal S304 is output as the determination signal S601. A composite signal of the determination signal S304 and the 2-frame motion determination signal S305 is output as the determination signal S601. The switching circuit 109 switches between the luminance signal S103Y for line-to-line calculation and the luminance signal S106Y for frame-to-frame calculation according to the motion determination signal S601. The switching circuit 110 switches between the color signal S103C for line-to-line calculation and the color signal S106C for frame-to-frame calculation according to the motion determination signal S601.

<Effect>
As described above, in the fifth embodiment, when the diagonal correlation detection circuit 104 determines that there is diagonal correlation, the output signal S304 of the motion determination circuit 304 is output as the determination signal S601 to the switching circuits 109 and 110, and the diagonal correlation is detected. When it is determined that there is no signal, the determination signal S304 from the motion determination circuit 304 and the determination signal S305 from the motion determination circuit 305 are combined and output to the switching circuits 109 and 110 as a determination signal S601. This also provides the same effect as the Y / C separation device in the first to fourth embodiments. That is, in the signals S100, S101, and S102 input to the 3-line YC separation circuit 103, the luminance signal component in the oblique direction is input to the line correlation YC separation circuit 103, and the line correlation output is not correctly separated by the line correlation YC separation circuit 103. Even if it leaks into the color signal S103C, when a diagonal line is input, it is possible to reduce the cross color in the output color signal S110 and improve the image quality by using the frame correlation YC separation.

(Sixth embodiment)
<Internal configuration of Y / C separation device 3>
FIG. 15 shows an internal configuration of the Y / C separation device 3 according to the sixth embodiment. The Y / C separation device 3 includes line memories 101, 102, 701, and 702, a frame memory 105, line correlation YC separation circuits 103 and 703, a frame correlation YC separation circuit 106, an oblique correlation detection circuit 104, Motion detection circuits 704 and 705, motion determination circuits 706 and 707, a synthesis circuit 708, and switching circuits 109 and 110 are provided.

  The line memory 701 delays the composite video signal S105 from the frame memory 105 by one horizontal period and outputs it as a composite video signal S701. The line memory 720 delays the composite video signal S701 from the line memory 701 by one horizontal period and outputs it as a composite video signal S702.

  The line correlation YC separation circuit 703 extracts the luminance signal S703Y and the color signal S703C based on the correlation (correlation between the three lines) between the composite video signals S105, S701, and S702.

  The motion detection circuit 704 detects the motion amount for each sample of the luminance signal from the difference between the luminance signals S103Y and S703Y between one frame, and outputs a signal S704 corresponding to the detected motion amount.

  The motion determination circuit 706 determines the presence or absence of motion of the luminance signal based on the signal S104 from the oblique correlation detection circuit 104 and the signal S704 from the motion detection circuit 704, and outputs a determination signal S706 according to the determination result.

  The motion detection circuit 705 detects a motion amount for each sample of color signals from the difference between the color signals S103C and S703C between one frame, and outputs a signal S705 corresponding to the detected motion amount.

  The motion determination circuit 707 determines the presence / absence of a color signal based on the signal S104 from the oblique correlation detection circuit 104 and the signal S705 from the motion detection circuit 705, and outputs a determination signal S707 corresponding to the determination result.

  The combining circuit 708 combines (OR operation) the determination signal S706 from the motion determination circuit 706 and the determination signal S707 from the motion determination circuit 707, and outputs the result as a determination signal S708.

  The switching circuit 109 outputs the luminance signal S103Y from the line correlation YC separation circuit 103 or the luminance signal S106Y from the frame correlation YC separation circuit 106 as the luminance signal S109 in response to the determination signal S708 from the synthesis circuit 708. The switching circuit 110 outputs the color signal S103C from the line correlation YC separation circuit 103 or the color signal S106C from the frame correlation YC separation circuit 106 as the color signal S110 in response to the determination signal S708 from the synthesis circuit 708.

<Operation of Y / C Separator 3>
Next, the operation of the Y / C separation device configured as described above will be described.

  The input composite video signal S100 obtains composite video signals S101 and S102 delayed by one line and two lines by the line memories 101 and 102, respectively. The input composite video signal S100 is delayed by one frame by the frame memory 105, and further, composite video signals S701 and S702 delayed by one line and two lines by the line memories 701 and 702 are obtained. The composite video signals S105, S701, and S702 between the three lines are band-limited by a line correlation YC separation circuit 703 by a bandpass filter having a pass frequency band centered at 3.58 MHz, respectively, and the correlation of the color signals between the three lines is further determined. A three-line correlated color signal S703C and a three-line correlated luminance signal S703Y are obtained by taking a majority vote or an intermediate value for determination.

  The motion detection circuit 704 detects the amount of motion of the luminance signal between one frame from the luminance signals S103Y and S703Y having a one-frame period difference, and a signal S704 corresponding to the detected amount of motion is output. The motion determination circuit 706 has the same configuration and operation as the motion determination circuit 108 described in the first embodiment, and attenuates or corrects the motion signal S704 according to the diagonal correlation detection signal S104. When an oblique component is detected, the motion determination result signal S706 is determined from a still image by attenuating the motion amount or increasing the threshold value for determining motion.

  The motion detection circuit 705 detects the amount of motion of the color signal between one frame from the color signals S103C and S703C having a one-frame period difference, and a signal S705 corresponding to the detected amount of motion is output. The motion determination circuit 707 has the same configuration and operation as the motion determination circuit 108 described in the first embodiment, and attenuates or corrects the motion signal S705 according to the diagonal correlation detection signal S104. When an oblique component is detected, the motion determination result signal S707 is determined from a still image by attenuating the amount of motion or increasing the threshold for determining motion.

  The luminance signal inter-frame motion determination signal S706 and the color signal inter-frame motion determination signal S707 are combined by the synthesis circuit 708 and output as a determination signal S708. The switching circuit 109 switches between the luminance signal S103Y for line-to-line calculation and the luminance signal S106Y for frame-to-frame calculation according to the determination signal S708. The switching circuit 110 switches between the color signal S103C for line-to-line calculation and the color signal S106C for frame-to-frame calculation according to the determination signal S708.

<Effect>
According to this embodiment, the diagonal correlation of the luminance signal component is detected by the diagonal correlation detection circuit 104 from the video signal between the three lines of the input composite video signal, and the detection result of the diagonal correlation detection circuit 104 is detected. In response, the output signal S704 of the luminance signal one-frame motion detection circuit 704 is attenuated or corrected by the luminance signal one-frame motion determination circuit 706 to perform motion determination from a still image and to detect one-frame motion of a color signal. In the signals S100, S101, and S102 input to the three-line correlation YC separation circuit 103, the output signal S705 of the circuit 705 is attenuated or corrected by the one-frame motion determination circuit 707 of the color signal and the motion is determined from the still image. The luminance signal component in the oblique direction is input to the line correlation YC separation circuit 103, and the line correlation YC separation circuit 1 3 is not correctly separated and leaks into the line correlation output color signal S103C, but when diagonal lines are input, the cross color is reduced in the output color signal S110 by using frame correlation YC separation. The image quality can be improved. In addition, the accuracy of motion detection can be improved by attenuating or correcting the motion detection result between frames according to the diagonal correlation detection result, so that the motion detection result is less likely to be erroneously detected when an oblique component is input. In addition, it is possible to improve the motion detection accuracy of the luminance signal with a difference of 1 frame and the motion detection accuracy of the color signal with a difference of 1 frame.

(Seventh embodiment)
<Internal configuration of Y / C separation device 3>
FIG. 16 shows an internal configuration of the Y / C separation device 3 according to the seventh embodiment. The Y / C separation device 3 includes a motion determination circuit 709 instead of the motion determination circuit 707 shown in FIG. Other configurations are the same as those of the Y / C separation device 3 shown in FIG. The motion determination circuit 709 compares the motion amount S705 detected by the motion detection circuit 705 with a fixed threshold value, and outputs a determination signal S709 according to the result. The combining circuit 708 combines (OR operation) the determination signal S706 from the motion determination circuit 706 and the determination signal S709 from the motion determination circuit 709, and outputs the result as a determination signal S708.

<Operation of Y / C Separator 3>
The operation of the Y / C separation device configured as described above will be described.

  The amount of motion is detected by the inter-frame motion detection circuit 704 from the luminance signal S103Y and the luminance signal S703Y having a one-frame period difference, and a one-frame motion signal S704 of the luminance signal is output. The 1-frame motion determination circuit 706 attenuates or corrects the motion signal S704 according to the diagonal correlation detection signal S104. When an oblique component is detected, the motion determination result signal S706 is determined from a still image by attenuating the motion amount or increasing the threshold value for determining motion.

  The motion amount is detected by the inter-frame motion detection circuit 705 for the color signal from the color signals S103C and S703C having a one-frame period difference, and the 1-frame motion signal S705 for the color signal is output. The motion determination circuit 709 compares the motion amount S705 detected by the motion detection circuit 705 with a fixed threshold value, and outputs a determination signal S709 according to the result.

  The synthesizing circuit 708 combines the luminance signal inter-frame motion determination signal S706 and the color signal inter-frame motion determination signal S709. The switching circuit 109 switches between the luminance signal S103Y for line-to-line calculation and the luminance signal S106Y for frame-to-frame calculation according to the determination signal S708. The switching circuit 110 switches between the color signal S103C for line-to-line calculation and the color signal S106C for frame-to-frame calculation according to the determination signal S708.

<Effect>
According to this embodiment, the diagonal correlation detection circuit 104 detects the diagonal correlation of the luminance signal component from the video signal between the three lines of the input composite video signal, and according to the detection result of the diagonal correlation detection circuit. Then, the output signal S704 of the luminance signal 1-frame motion detection circuit 704 is attenuated or corrected by the luminance signal 1-frame motion determination circuit 706 to perform motion determination from the still image, and the color signal 1-frame motion determination circuit. By using the output signal S709 of 709, in the signals S100, S101, S102 inputted to the 3-line YC separation circuit 103, the luminance signal component in the oblique direction is inputted to the line correlation YC separation circuit 103, and the line correlation YC separation circuit Even if it is not correctly separated at 103 and leaks into the line correlation output color signal S103C, If is entered in a cross color reduction in a color signal S110 outputted by the from frame correlation YC separation, it is possible to improve the image quality. Also, by attenuating or correcting the inter-frame motion detection result of the luminance signal according to the oblique correlation detection result, the accuracy of the luminance signal motion detection can be improved from the difference of one frame, and an oblique component is input. In this case, it is possible to prevent the motion detection result from being erroneously detected, and to improve the motion detection accuracy of the luminance signal of one frame difference.

(Eighth embodiment)
<Internal configuration of Y / C separation device 3>
FIG. 17 shows an internal configuration of the Y / C separation device 3 according to the eighth embodiment. The Y / C separation device 3 includes a motion determination circuit 710 instead of the motion determination circuit 706 shown in FIG. Other configurations are the same as those of the Y / C separation device 3 shown in FIG. The motion determination circuit 710 compares the motion amount S704 detected by the motion detection circuit 704 with a fixed threshold value, and outputs a determination signal S710 according to the result. The combining circuit 708 combines (OR operation) the determination signal S710 from the motion determination circuit 710 and the determination signal S707 from the motion determination circuit 707, and outputs the result as a determination signal S708.

<Operation of Y / C Separator 3>
The operation of the Y / C separation device configured as described above will be described.

  A motion amount detection circuit 704 detects the amount of motion from the luminance signals S103Y and S703Y having a one-frame period difference, and outputs a one-frame motion signal S704 of the luminance signal. The motion determination circuit 710 compares the motion amount S704 detected by the motion detection circuit 704 with a fixed threshold value, and outputs a determination signal S710 according to the result.

  The motion amount is detected by the inter-frame motion detection circuit 705 for the color signal from the color signals S103C and S703C having a one-frame period difference, and the 1-frame motion signal S705 for the color signal is output. The 1-frame motion determination circuit 707 attenuates or corrects the motion signal S705 in accordance with the diagonal correlation detection signal S104. When an oblique component is detected, the motion determination result signal S707 is determined from a still image by attenuating the amount of motion or increasing the threshold for determining motion.

  The synthesizing circuit 708 combines the luminance signal inter-frame motion determination signal S710 and the color signal inter-frame motion determination signal S707. The switching circuit 109 switches between the luminance signal S103Y for line-to-line calculation and the luminance signal S106Y for frame-to-frame calculation according to the determination signal S708. The switching circuit 110 switches between the color signal S103C for line-to-line calculation and the color signal S106C for frame-to-frame calculation according to the determination signal S708.

<Effect>
According to this embodiment, the diagonal correlation of the luminance signal component is detected by the diagonal correlation detection circuit 104 from the video signal between the three lines of the input composite video signal, and the detection result of the diagonal correlation detection circuit 104 is detected. Accordingly, the output signal S705 of the color signal 1-frame motion detection circuit 705 is attenuated or corrected by the motion determination circuit 707 to perform motion determination from the still image, and the output signal of the luminance signal 1-frame motion determination circuit 710 By using S710, in the signals S100, S101, and S102 inputted to the three-line YC separation circuit 103, the luminance signal component in the oblique direction is inputted to the line correlation YC separation circuit 103 and correctly separated in the line correlation YC separation circuit 103. Even if the line correlation output color signal S103C is leaked and the diagonal line is input, Can is that by More frame correlation YC separation, the cross-color reduction in a color signal S110 outputted, improve the image quality. In addition, by attenuating or correcting the inter-frame motion detection result of the color signal according to the oblique correlation detection result, the accuracy of the color signal motion detection can be improved from the 1-frame difference, and an oblique component is input. In this case, it is possible to prevent the motion detection result from being erroneously detected, and it is possible to improve the motion detection accuracy of the color signal by one frame difference.

(Ninth embodiment)
<Internal configuration of Y / C separation device 3>
FIG. 18 shows an internal configuration of the Y / C separation device 3 according to the ninth embodiment. The Y / C separation device 3 includes motion determination circuits 710 and 709 and a selector 1001 instead of the motion determination circuits 706 and 707 and the synthesis circuit 708 shown in FIG. Other configurations are the same as those of the Y / C separation device 3 shown in FIG. The motion determination circuits 710 and 709 compare the motion amounts S704 and S705 detected by the motion detection circuits 704 and 705 with a fixed threshold value, and output determination signals S710 and S709 according to the results. The selector 1001 outputs the determination signal S710 from the motion determination circuit 710 to the switching circuits 109 and 110 as the determination signal S1001 when the signal S104 from the diagonal correlation detection circuit 104 indicates “with diagonal correlation”, and the diagonal correlation detection circuit When the signal S104 from 104 indicates “no diagonal correlation”, the determination signal S710 from the motion determination circuit 710 and the determination signal S709 from the motion determination circuit 709 are combined (OR operation) and used as a determination signal S1001 as a switching circuit. 109 and 110.

<Operation of Y / C Separator 3>
The operation of the Y / C separation device configured as described above will be described.

  The motion detection circuit 704 detects the amount of motion from the luminance signals S103Y and S703Y having a one-frame period difference, and outputs a one-frame motion signal S704 of the luminance signal. The motion determination circuit 710 compares the motion amount S704 detected by the motion detection circuit 704 with a fixed threshold value, and outputs a determination signal S710 according to the result.

  The motion detection circuit 705 detects a motion amount from the color signals S103C and S703C having a one-frame period difference, and outputs a one-frame motion signal S705 of the color signal. The motion determination circuit 709 compares the motion amount S705 detected by the motion detection circuit 705 with a fixed threshold value, and outputs a determination signal S709 according to the result.

  The motion determination signals S710 and S709 are output by the selector 1001 when the diagonal correlation is present, and the motion determination signal S710 is output as the determination signal S1001, and when there is no diagonal correlation, the combined signal of the motion determination signals S710 and S709 is output as the determination signal S1001. Is done. The switching circuit 109 switches between the luminance signal S103Y for line-to-line calculation and the luminance signal S106Y for frame-to-frame calculation according to the motion determination signal S1001. The switching circuit 110 switches between the color signal S103C for line-to-line calculation and the color signal S106C for frame-to-frame calculation in accordance with the motion determination signal S1001.

<Effect>
As described above, in the ninth embodiment, when the diagonal correlation detection circuit 104 determines that there is diagonal correlation, the output signal S710 of the motion determination circuit 710 is output as the determination signal S1001 to the switching circuits 109 and 110, and the diagonal correlation is detected. When it is determined that there is none, the determination signal S710 from the motion determination circuit 710 and the determination signal S709 from the motion determination circuit 709 are combined and output to the switching circuits 109 and 110 as a determination signal S1001. Also by this, the same effect as the Y / C separation device in the sixth to eighth embodiments can be obtained. That is, in the signals S100, S101, and S102 input to the three-line YC separation circuit 103, the luminance signal component in the oblique direction is input to the line correlation YC separation circuit 103, and the line correlation output is not correctly separated by the line correlation YC separation circuit 103. Even if it leaks into the color signal S103C, when a diagonal line is input, it is possible to reduce the cross color in the output color signal S110 and improve the image quality by using the frame correlation YC separation.

(Tenth embodiment)
The configuration of the noise reduction device according to the tenth embodiment is shown in FIG. This noise reduction apparatus includes a line memory 101, 102, a frame memory 105, a noise reduction circuit 1601, 1602, an oblique correlation detection circuit 104, a motion detection circuit 107, a motion determination circuit 108, and a switching circuit 1603. Prepare.

  The operation of the noise reduction device configured as described above will be described.

  The input video signal S100 is delayed by the line memories 101 and 102 and input to the noise reduction circuit 1601 using the correlation between the lines. As a configuration of the noise reduction circuit 1601, a method of taking a signal difference between lines and subtracting a difference value from a reference signal to reduce a noise component, or a method of averaging noise signals between lines to reduce a noise component and so on. Also, the noise reduction circuit 1602 receives signals S101 and S105 having a one-frame delay difference, and reduces noise using the correlation between frames. As a configuration of the noise reduction circuit 1602, a method of taking a difference value of a signal between frames and subtracting the difference value from a reference signal to reduce noise, a method of averaging a signal of a difference between frames and reducing a noise component, etc. There is. The output S1601 of the noise reduction circuit 1601 and the output S1602 of the noise reduction circuit 1602 are switched according to the output signal S108 of the motion determination circuit 108. When the determination signal S108 indicates a still image (no motion), the switching circuit 1603 selects the output signal S1602 of the noise reduction circuit 1602 and outputs it as a signal S1603, and when the determination signal S108 indicates a moving image (with motion). The output signal S1601 of the noise reduction circuit 1601 is selected and output as a signal S1603.

  According to this embodiment, the diagonal correlation of the luminance signal component is detected by the diagonal correlation detection circuit 104 from the video signal between the three lines of the input video signal, and according to the detection result of the diagonal correlation detection circuit 104. The output signal S107 of the motion detection circuit 107 is attenuated or corrected by the motion determination circuit 108, and the motion is determined from the still image, so that the image is output while suppressing the image quality deterioration such as the image blurring in the vertical direction on the diagonal line. Noise can be reduced in an image including a lot of oblique components in the signal S1603.

  Note that the present embodiment can be modified in the same manner as the first embodiment is transformed into the second to ninth embodiments, and thus the same as in the second to ninth embodiments. The effect is obtained.

  The motion detection device of the present invention can be applied to a Y / C separation device or a noise reduction device. Furthermore, the present invention can be applied to a television receiver, a liquid crystal television, a plasma display television, an organic EL television, a video capture board device, a personal computer device, a video cassette recorder and the like equipped with these.

FIG. 1 is a block diagram illustrating an overall configuration of a television receiver according to a first embodiment. It is a block diagram which shows the internal structure of the Y / C separation apparatus shown in FIG. FIG. 3 is a block diagram showing an internal configuration of an oblique correlation detection circuit shown in FIG. 2. FIG. 3 is a block diagram illustrating an example of an internal configuration of a motion determination circuit illustrated in FIG. 2. FIG. 5 is a diagram for explaining an operation of motion determination by the motion determination circuit shown in FIG. 4. It is a wave form diagram for demonstrating operation | movement when a diagonal line is input into the YC separation apparatus shown in FIG. FIG. 3 is a block diagram showing another example of the internal configuration of the motion determination circuit shown in FIG. 2. 6 is a flowchart illustrating a flow of determination processing according to still another example of the motion determination circuit illustrated in FIG. 2. It is a block diagram which shows the internal structure of the Y / C separation apparatus by 2nd Embodiment. 10 is a flowchart illustrating a flow of determination processing by an example of the motion determination circuit illustrated in FIG. 9. 10 is a flowchart illustrating a flow of determination processing according to another example of the motion determination circuit illustrated in FIG. 9. It is a block diagram which shows the internal structure of the Y / C separation apparatus by 3rd Embodiment. It is a block diagram which shows the internal structure of the Y / C separation apparatus by 4th Embodiment. It is a block diagram which shows the internal structure of the Y / C separation apparatus by 5th Embodiment. It is a block diagram which shows the internal structure of the Y / C separation apparatus by 6th Embodiment. It is a block diagram which shows the internal structure of the Y / C separation apparatus by 7th Embodiment. It is a block diagram which shows the internal structure of the Y / C separation apparatus by 8th Embodiment. It is a block diagram which shows the internal structure of the Y / C separation apparatus by 9th Embodiment. It is a block diagram which shows the structure of the noise reduction apparatus by 10th Embodiment. It is a block diagram which shows the structure of the conventional motion processing circuit. It is a wave form diagram explaining operation | movement of the conventional motion processing apparatus. Waveform diagram explaining the operation when diagonal lines are input to a conventional motion processing device

Explanation of symbols

101, 102, 701, 702 Line memory 103, 703 Line correlation YC separation circuit 104 Oblique correlation detection circuit 105, 300 Frame memory 106 Frame correlation YC separation circuit 107, 301, 704, 705 Motion detection circuit 109, 110, 1603 switching circuit 201-203 Band limiting filters 204, 205 Adders 206, 207 Delay circuits 208, 209 Subtract circuits 210, 211 Absolute value circuits 212, 213 Comparison circuits 214 OR circuits 108, 302, 304, 305, 706, 707, 709, 710 Motion determination circuits 303 and 708 synthesis circuits 601 and 1001 selectors 1601 and 1602 noise reduction circuits

Claims (26)

An oblique correlation detector for detecting a correlation (oblique correlation) in the oblique direction of the composite video signal;
A motion detector that detects a motion amount based on the inter-frame difference of the composite video signal;
A motion determination unit that determines the presence or absence of motion in the composite video signal based on the amount of motion detected by the motion detection unit;
The movement determination unit
Determining the presence or absence of the movement in consideration of the detection result of the diagonal correlation by the diagonal correlation detection unit,
A motion detection apparatus characterized by that. In claim 1,
The movement determination unit
A threshold value of a level corresponding to the detection result of the diagonal correlation by the diagonal correlation detection unit is set, and the presence or absence of the motion is determined by comparing the amount of motion detected by the motion detection unit with the threshold value. To
A motion detection apparatus characterized by that. In claim 1,
The movement determination unit
Correcting the amount of motion detected by the motion detector according to the detection result by the oblique correlation detector, and determining the presence or absence of the motion by comparing the corrected amount of motion with a predetermined threshold;
A motion detection apparatus characterized by that. In claim 1,
The movement determination unit
When the amount of motion detected by the motion detector is greater than a predetermined threshold, it is determined that there is motion, and when the amount of motion is less than the predetermined threshold, the oblique correlation detector Determine the presence or absence of movement according to the detection result of the diagonal correlation,
A motion detection apparatus characterized by that. In claim 1,
The motion detector is
A first motion detection circuit for detecting a motion amount based on a difference between the frames of the composite video signal;
A second motion detection circuit that detects a motion amount based on a difference between the two frames of the composite video signal;
A motion detection apparatus characterized by that. In claim 1,
The motion detector is
A first motion detection circuit that detects a motion amount based on a difference between one frame of luminance signals extracted from the composite video signal by luminance signal / color signal separation using line correlation;
A second motion detection circuit that detects a motion amount based on a difference between one frame of color signals extracted from the composite video signal by luminance signal / color signal separation using the line correlation.
A motion detection apparatus characterized by that. In claim 5 or 6,
The movement determination unit
A first motion determination circuit that determines the presence or absence of motion in the composite video signal based on the amount of motion detected by the first motion detection circuit;
A second motion determination circuit that determines the presence or absence of motion in the composite video signal based on the amount of motion detected by the second motion detection circuit.
A motion detection apparatus characterized by that. In claim 7,
The first and / or second motion determination circuit includes:
Determining the presence or absence of the movement in consideration of the detection result of the diagonal correlation by the diagonal correlation detection unit,
A motion detection apparatus characterized by that. In claim 5 or 6,
The movement determination unit
Switching between the first determination and the second determination according to the detection result of the diagonal correlation by the diagonal correlation detector,
The first determination is:
Determining the presence or absence of the motion based on the amount of motion detected by the first motion detection circuit;
The second determination is as follows:
The presence or absence of the motion is determined based on the amount of motion detected by the first motion detection circuit and the amount of motion detected by the second detection circuit.
A motion detection apparatus characterized by that. A first luminance signal / color signal separation unit that extracts a first luminance signal and a first color signal from the composite video signal using line correlation;
A second luminance signal / color signal separating unit that extracts a second luminance signal and a second color signal from the composite video signal using frame correlation;
A motion detection device according to any one of claims 1 to 9,
The first luminance signal and the second luminance signal are combined according to a determination result by the motion determination unit of the motion detection device and output as a third luminance signal, and the first color signal and the first luminance signal are output. And a switching unit that combines the two color signals according to the determination result by the motion determination unit of the motion detection device and outputs the resultant as a third color signal.
A luminance signal / color signal separation device characterized by the above. A first luminance signal / color signal separation unit that extracts a first luminance signal and a first color signal using line correlation of the current frame of the composite video signal;
A second luminance signal / color signal separation unit that extracts a second luminance signal and a second color signal using line correlation of a previous frame of the composite video signal;
A motion detection device according to any one of claims 6 to 9,
The first luminance signal and the second luminance signal are combined according to a determination result by the motion determination unit of the motion detection device and output as a third luminance signal, and the first color signal and the first luminance signal are output. And a switching unit that combines the two color signals according to the determination result by the motion determination unit of the motion detection device and outputs the resultant as a third color signal.
A luminance signal / color signal separation device characterized by the above. A first noise reduction unit that reduces noise of the composite video signal using line correlation;
A second noise reduction unit for reducing noise of the composite video signal using frame correlation;
A motion detection device according to any one of claims 1 to 9,
A switching unit that synthesizes and outputs the video signal obtained by the first noise reduction unit and the video signal obtained by the second noise reduction unit according to a determination result by the motion determination unit of the motion detection device. With
The noise reduction apparatus characterized by the above-mentioned. Detecting a correlation (diagonal correlation) in an oblique direction of the composite video signal;
Detecting the amount of motion based on the inter-frame difference of the composite video signal; and
(C) determining whether or not there is movement in the composite video signal based on the amount of movement detected in step (b),
In step (c),
The presence or absence of the movement is determined in consideration of the detection result of the diagonal correlation in the step (a).
A motion detection method characterized by the above. In claim 13,
In step (c),
A threshold value of a level corresponding to the detection result of the diagonal correlation in the step (a) is set, and the presence / absence of the motion is determined by comparing the motion amount detected in the step (b) with the threshold value. judge,
A motion detection method characterized by the above. In claim 13,
In step (c),
The amount of motion detected in step (b) is corrected according to the detection result in step (a), and the presence or absence of the motion is determined by comparing the corrected amount of motion with a predetermined threshold value. ,
A motion detection method characterized by the above. In claim 13,
In step (c),
When the amount of motion detected in the step (b) is larger than a predetermined threshold, it is determined that “there is motion”, and when the amount of motion is smaller than the predetermined threshold, the step (a) Determine the presence or absence of movement according to the detection result of the diagonal correlation by
A motion detection method characterized by the above. In claim 13,
The step (b)
Detecting the amount of motion based on the inter-frame difference of the composite video signal (d);
Detecting the amount of motion based on the difference between the two frames of the composite video signal (e),
A motion detection method characterized by the above. In claim 13,
The step (b)
Detecting a motion amount based on a difference between one frame of luminance signals extracted from the composite video signal by luminance signal / color signal separation using line correlation;
And (e) detecting a motion amount based on a difference between one frame of color signals extracted from the composite video signal by luminance signal / color signal separation using the line correlation.
A motion detection method characterized by the above. In claim 17 or 18,
The step (c)
Determining whether or not there is motion in the composite video signal based on the amount of motion detected in step (d);
(G) determining the presence or absence of motion in the composite video signal based on the amount of motion detected in step (e).
A motion detection method characterized by the above. In claim 19,
In step (f) and / or (g),
The presence or absence of the movement is determined in consideration of the detection result of the diagonal correlation in the step (a).
A motion detection method characterized by the above. In claim 17 or 18,
In step (c),
Switching between the first determination and the second determination according to the detection result of the diagonal correlation in the step (a),
The first determination is:
Determining the presence or absence of the movement based on the amount of movement detected in step (d),
The second determination is as follows:
The presence or absence of the motion is determined based on the amount of motion detected in step (d) and the amount of motion detected in step (e).
A motion detection method characterized by the above. (H) extracting a first luminance signal and a first color signal from the composite video signal using line correlation;
(I) extracting a second luminance signal and a second color signal from the composite video signal using frame correlation;
The motion detection method according to any one of claims 13 to 21,
The first luminance signal and the second luminance signal are combined according to the determination result in step (c) of the motion detection method and output as a third luminance signal, and the first color signal and the Combining the second color signal with the determination result in step (c) of the motion detection method and outputting as a third color signal (j).
A luminance signal / color signal separation method. Extracting a first luminance signal and a first color signal using line correlation of the current frame of the composite video signal;
(1) extracting a second luminance signal and a second color signal using line correlation of the previous frame of the composite video signal;
The motion detection method according to any one of claims 18 to 21,
The first luminance signal and the second luminance signal are combined according to the determination result in step (c) of the motion detection method and output as a third luminance signal, and the first color signal and the Combining the second color signal with the determination result in step (c) of the motion detection method and outputting as a third color signal (m).
A luminance signal / color signal separation method. Reducing noise of the composite video signal using line correlation (n);
(O) reducing noise of the composite video signal using frame correlation;
The motion detection method according to any one of claims 13 to 21,
A step (p) of synthesizing and outputting the video signal obtained in step (n) and the video signal obtained in step (o) according to the determination result in step (c) of the motion detection method; Comprising
The noise reduction method characterized by the above-mentioned. A motion detection device according to any one of claims 1 to 9, a luminance signal / color signal separation device according to claim 10 or 11, and a noise reduction device according to claim 12. Prepare
A video display device characterized by that. A motion detection method according to any one of claims 13 to 21, a luminance signal / color signal separation method according to claim 22 or 23, and a noise reduction method according to claim 24. Prepare
A video display method characterized by the above.

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